Cape Town - Spam is at its lowest level this year, reducing the likelihood of malicious software spreading by e-mail, a security company has said.
"In the last month, we saw a further reduction in the amount of spam found in e-mail traffic - its share was down 3.4 percentage points, and fell to its lowest point since the start of the year - 73.8%," said Kaspersky Lab.
The company warned users that continued vigilance is important and that one should avoid opening suspicious e-mail attachments.
Some malicious software is even able to spread itself from a user's account without their consent or knowledge.
The Russian-based company said that most of the latest unsolicited mail originates in China and followed a pattern of trying to fleece users out of money.
"It is safe to say that these e-mails from Chinese "manufacturers" or "suppliers" are part of a new type of fraud based on "Nigerian" spam - the fraudsters are actively exploiting the growing interest investors have in the Chinese market.
"They target businessmen looking for contacts with Chinese manufacturers, and connect them with scammers who make off with their money and are never heard of again."
Spam is a global problem and by some estimates, makes up about 85% of e-mail traffic. The practice has also spread to social networking sites as well as instant messaging platforms.
Frequently, spammers target users with commercial messages that are often sent automatically by infecting host computers with malicious software.
Traditionally, new spam is triggered by a global event such as the death of singer Whitney Houston, or is specific to a country.
Many South Africans were targeted with spam of a Nigerian stuck on the ISS after Mark Shuttleworth became the first person on the continent to go into space in 2002.
Spam traffic might be on the decline as hackers turn their attention to platforms like Facebook. The social network has become a prime target for malicious software which could then propagate and send itself to a user's friend list.
A further risk is that the software could turn a user's machine into a so-called zombie - a computer under a hacker's control. This could be used as part of a botnet to crash company servers and blackmail the owners.
"In May, the proportion of spam in mail traffic decreased considerably. This could be down to a seasonal fluctuation. If that is the case, spam will remain at a low level until August. However, this may be a systemic phenomenon, and in that case the share of spam in mail traffic will soon drop below 70%," said Maria Namestnikova, Kaspersky Lab's senior spam analyst.